Spring suspension for vehicles



' April 12, 192% 1,623,986

F. L, O. WADSWORTH SPRING SUSPENSION FOR VEHICLES Filed Jan. 20. 1921 5 Sheets-Sheet' 1 E. 1,' f' i 6 -4 1 U'" l El l l v n u:

-4 Trek/Vfl( Apr-il 12, 1927.

F. L. C. WADSWORTH SPRING .SUSPENSIONT'OR VEHICLES Filed Jan, 2o. i921 5 sheets-sheet 2 A ril 12 1927. 1,623,986

p F., l.. o. wADswoRTH SPRING SUSPENSlON FOR VEHICLES Filed Jan. 2o, 1921 5 'sheets-sheet s F. L. o. wADswo'IRTH April 12, 1921. 1,623,986

SIRIG:Y SUSPENSION FOR VEHICLES Filed Ja 29. 1921 5 Sheets-Sheet 4 April ,12' 1927. mamma F. Lo. WAmsvvcwnf` SPRING SUSPENSION FOR VEHLE'S Filed Jem. 20. 1921 5 Smets-#heet 5,

arrow/Mx Patented Apr. 12, 1927.

terasse- @FEMS-E.

FRANK I1. 0. WADSXVORTII, OF PITTSBURGH, PENNSYLVANIA.

SPRING SUSPENSION FOR VEHICLES.

Application filed. January 20, 1921.

My invention relates to elastic shock absorber organizations of the multiple supplemental spring type, in which one of the secondary resilient elements of the combination is utilized to assist in resisting and absorbing the effects of kinetic compression shocks, and another structurally independent spring is employed to resist and restrain the disagreeable and ofttimcs dangerous rebound and ctossing action that results fromthe recoil or separation of the spring connected parts. Organizations of this character are generally referred to as counteracting-spring systems, for the reason that the elastic eler ments which respectively resist the closing or the compression, and the expansion or rebound, of the relatively movable members, act in opposite directions, and are generally so connected as to oppose each other in the intermediate or central portions of the oscillatory movement. As contrasted with a single-actingsupplemcantal-springF systemwhich is only adapted to assist in restraining one way displacements (either of compression or separation) from normal load positiona counteracting spring suspension presents the advantage of securing a more rapid and effective checking and absorption of the recoil or returnoscillations of the stressed parts; and as contrasted with a doubleacting-supplemental-spring construction-which utilizes the direct or the reversed lexure of the same resilient member to check the double movements, of both compression and rebound, from Jthe loci of static equilibrium-the counteracting-spring-system presents the possibility of securing; a wider range of relative restraint to the reversed movements ot the suspended parts, and of also utilizing different forms, as well as different strengths, ot spring elements for respectively resisting the eii'ect of compressive shocks and of recoil and rebound stresses. The counteracting-supplemental-spring combination also possesses the advantage of heing `able to eiiciently perform certain of its intended `functions even when one oi its resilient elements is injured or destroyed. On the other hand, the usual forms o counteracting-spring construction heretofore used, are open to the objectionthat the elastic restraining action of both elements .is diminished-and for certain parts of the oscillatory movement is entirely destroyed--by the balanced effect of the opposing springs;

Serial No. 438,597.

normal load stresses) is disturbedby any injury to, or relative weakening of, one oi the dual balancing; elements. Y

One of the purposes of my present invention is to produce a counteraating-spring;l combination which has all of the advantages ordinarily presented by this type of construction, and which is free from the objection last mentioned. In order that this feature of my improvements may be more easily and clearly understood I will first briefiy refer to Figs. l to 6 of my drawings which illustrate diagrammatically the usual action of an ordinary counteracting-spring system and the manner in which this action is characteristically modified by the application of my invention thereto. In these illustrations, 1 indicates a member that may be attached to, or oscillated by, one of the relatively movable parts of `a chassis frame-e. g., the body or tonneau member thereof--Q-Z indicate members that are Vcarried on the other of the said relatively c movable parts*e. g., on the aXle frameditions the elastic system does not offer any substantial resistance to small displacements oi the parts in either direction. In other words. there is a certain range or tleld of oscillatory movement. on the two sides of position A, within which the balanced springrcombination is inoperative, or

ineffective` in checking or restrainingr the relative displacement of the spring connected members. When the body supports `(l) are subjected to load stress they are forced toward the axle frame members (2) thereby compressing: the spring, 3, and permittingf the opposing spring` 4 to expand. Under a normal fixed load the parts of the system will assume a position of static equilibrium, B'. which is diagrammatically illus trated in Fig. 2, in which the imposed tension on the lower spring 8 just balances the combined compression stress of the fixed and the position of static equilibrium (under loadV and the residual expansion stress of lll Fig. 7 is a rear elevation ot the lett hand side et the rear cross lealv spring: suspension ot a Ford car; equipped with one toi-m ot my new shock alzisorber organization; Figi'. 8 is a similarI View ot the right hand side of the construction shown in Figi'. T, but with the parts inV the position which they assume under compressive shocks; Fipg. l) is an enlargeifl sectional. elevation on the plane l)-9 olf Fig. ILO-ot this same construction with the parts in rebound position; Fig. 10 is a Vsectionalelevation on the plane 10-10 of Fig. 9; Fig. l1 is a iront view of another exemplitication et my iniprovements as applied to a front cross leai' sprino'; and Fig. 12 is a partial cross section `on the plane ie--ie of rig. n.

Fig. 13 illustrates a third form of my improved spring; structure mounted on the liront axle support 0i a Ford ear; Fig'. 14 is another view of this saine structnre show ing the parts in the position which they assume under kinetic compression shocks; 15 is a partial sectional elevation on the central vertical planewi. e.7 the plane 1li-15 ot the construction shor-.in in 1G; with the .members thereo'l in rebound position; Fig'. 1G is a cross sectional view on the plane 16-16 of Fig. 15; Fig'. 17 is an elevation oi another multiple spring suspension iter' the rear axle support ol a Ford car; Fig. 18 is a vertical section on the plane 18-18 oil" Fig. 17; and Fig. A19 is a central sectional elevation of this construction (as on the plane 19-19 et F ig. 18) showing the position and action of the parts when sub- `jeeted to kinetic compression shocks.

Fig. 2O is a sid-e elevationw-partly in sectionof a fifth illustrative embodiment of my invention as applied to an ordinary full elliptic leaii spring' suspension; Fig. 21 is a second view ot a portion ot the structure shown in Fig. 20, with the parts thereof in the position which they assume under an increased compression stress; Fig. 22 illustrates an application of my improvements to a semi-elliptic side leaf spring support; Fig. 23 is another vienr oit this saine construction showing1 the action oil' the mechanism in resisting; displacen'ients in either direction from the normal load position ot' Fig'. 22; Fig. 23 is a sectional elevation on the plane 2-1-24E oit Fig. 22; Fie'. 25 is a View, similar' to that'ol2 Fig. 20, and illustrates an embodi ment of my invention ina threeouarterelliptic, or scroll7 spring suspension system; F ig'. 26 is a partial side elevation ot the structure shown inFig. 25 with the parts in the position which they occupy When under kinetic compression; and F ig'. 2T is a sectional elevation on the plane 27-27 of Fig. 25.

Fig. 28 is a rear viewwin partial section on `the central vertical plane et the spring suspension-shovving,l another species oi my generic invention applied to a cross lea't main spring; Figi'. 29 is an elevation ot this embodiment ot my multiple auxiliary spring; construction and shoivs the action oit the parts thereol when they rebound 'troni the normal load iosition that is depicted, in 'lull lines. in Fie'. 2S; Fin'. 30 ,is a detail sectional view on the plane EEO- 30 ot Fin'. 2li; Fini. 3l

a sectional elevation ol another embodi- .nient ot my improvements in a semi-elliptic side leal"V spring.;l suspension; Fig, 32 a View, similar to that ot Fig. 3l. showinpv the parts of that structure in the position which they occupy when subjected to an increased compressive stress; Fig. is a side elevation Which illustrates the section of this saine mechanism When the members thereof rebound from the posit-ions shown in Finns. 3l and 82; Fig, 341; is a sectional elevationsiinilar to those ot' Figs. 31 and 32-ot another imultipleleaf-sturing organization that embodies my improvements; F ig'. 85 is also a sectional elevation (on the central vertical plane 35-35 ot Fig', 36u), that illustrates the application ot my invention to a cantilevenleatspringi suspension 'tor either the rear or the Afront asile ot a. motor vehicle: F a partial side elevation of the constretion shown in Fig'. 35 with the parte thereo'l' in rebound posit-ion; and Figa'. 3G is an, enlarged detail View ot a portion of the structure depicted in Figs. and 36.

Fie'. 37 is another sectional view-on the central. vertical plane through a cross leal" spring support-which illutratesa further embodiment of my pgeneric improvements: Fig'. 38 a front elevation ot this construction and shows the action ot the system when the parts rebound above the normal load position ot Fig'. 3i" (tull. lines) Fie'. 3) is a view, similar to that o't Fin'. 37, ot another exemplitieation ot niy invention; Figi. Ll() is a rear eleif'ation ot the organization shown in Fig. 89 With the parts in rebound position; Fig'. lll is composite sectional elevationpartlyv on the central rertical plane ot the suspension system and partly on the plane Ll1-l1 of Fig. i3-Which illustrates still another utilization oli my improvenients in a semi-elliptic side leaf spring' suspension; Fin'. is a side elevation showing' the parts of Fig' l1 in the position assumed by themv under rebound stress; Fie' i3 is a sectional view` on the plane di-43 ot ll--l-2; Figi'. tlis a side elevation-partly .in section-ot` a 'further illustrative embodiment ot my prei-:entiniprovenients as applied to a threequarter-elliptic spring support; and Fig. a5 is a sectional elevation illustrating' the use ot certain 'features ol my in vention in conjunction with a semi-elliptic side lealz spring'.

'llhe construction shown En Figs. 7-8-9 and l0 oit." my drawings coniprises tivo pair oit conical volute, or bcehive springs 3--3 lill axle parts imposes a rapidly increased liexauxiliary springs 3 and 4, which are mount` ure on the main spring-which is then concurrently lifted at its center and ends and pressed downward at the points on which the bracketsi'wl' aremount-ed-and this will very quickly arrest and absorb the final effects of an abnormal overthrow or re bound of the suspension system.

The outer' arms of the lever member 8 may be provided with a slot, or with a series of holes, (as indicated in dotted lines in Fig. 9) for the purpose of varying the position of the pivot bolt 26, and thereby altering the relation between the separation of the body and axle members and the resultant angular swing of the lever. This alteration will in turn vary the relative movement of the center and ends of the main spring, and thereby modify the ratio of the concurrent llexures of the primary and secondary elastic elements; but in all cases the kineinatical arrangement is suoli that all of the springsthe main leaf spring as well as the helical coil supplemental springen-are maintained under some initial compression and are prevented from ever retelling or expanding beyond that position of predetermined initial iexure. The result of this arrangement is 'that the elastically suspended parts are not subjected to the usual tossing7 action that follows the sudden lexing and subsequent reverse recoil and overthrow of free unrestained spring supports; but are, on the contrary always held against any displacement from the normal position of static balance by the positive flexural resistance of the main spring and of one of the sets of supplemental springs. rind the utilization of two, or more, auxiliary elastic elements, for separately rest-raining and checking compression and rebound actions, makes it possible to impose, if desired, a widely varied resistance to those respective movements without altering the form or character of the usual main spring suspension' members. ln general l prefer to make the rebound-check supplcniental'vspring member considerably stronger, or stiffer, than the counteracting auxiliary member which resists compression-e. g., by making the springs, amel, of heavier wire, or by reinforcing them by additional inner coils as shown in Fig, lO-for the joint purposes of securing a powerful and quick restraint on rebound movements without sacrificing the desired sensitiveness of the system under compressive shocks, and of also exercising a magnilied reaction pressure on the intermediate flexible portions of the main spring and thereby more effectually preventing any possible reflexing or expan sion of this member beyond its normal load form.

The construction shown in Figs. 1l and l2 corresponds very closely to that first described. lt comprises two counteracting ed on a common bracket support a-i, that is clipped to an intermediate portion of the main spring l at a point about midway its center and end. These springs are maintained under a predetermined initial tension, and prevented" from expanding beyond the normal load position shown in Fig. 11, b means of the -two pairs of bolts 17a-17, and 2828, which are connected at their opposite ends with the two follower plates 20a and 13-by means of the cross bars or yokes, 3l, 32, respectively-and are provided with heads and collars (marked and 3st respectively) that engage with the bracket clip 7 and limit the longitudinal movement of the said bolts with respect thereto. These bolts are also provided with a second set of heads and collars 36 and 37 which are so positioned as to be engaged by the forked inner ends 38 of double arm lever 8u. This lever member is pivotally supported, at an intermediate point in its length, on the axle perch bolt ll, and is coupled at its outer end to the extremity of the main spring (by shackle links 2F), and also to the body of the vehicle by the adjustable rod and bracket link connectors 222339.

The axes of the counteracting auxiliary springs, 3 and ela, are preferably offset, as shown in Fig. ll, for the double purpose of enabling` their bases to be brought nearer together, and of increasing the effective resistance of the rebound-clieck-spring an to the angular movement of the lever 8a. The elastic restraint resistance of the upper auxiliary spring is further augmented by the addition of the inner coil l0 (as shown in section in F ig. 12) so that this system-like that shown in Figs. 7 to l0 inclusive-will impose a considerably greater check on any rebound oscillation (and will also act more strongly in limiting the reflexing or expansion of the main spring) than it does on compression movements.

The functional operation of the combination last `described is precisely the same as that of the construction first considered, and does not, for that reason, require any extended explanation. )V hen the body and axle parts approach each other the lever 8 is rocked upwardly on its axle bolt support and lifts the lower follower plate 20athereby compressing the spring 3 against the under face of the main spring l-until the collars engage with the base plate of the upper spring and thereby lock the bolts 1T against further sliding movement there through. In this action the bracket 23 swings outwardly on its pivot bolt 39 to accommodate the longitudinal movement of the connector 22a. When the body and axle parts separate from one another-(beyon ;l the position of static balance shown in Fig. 11)the bracket is locked against its body support and anupward pullV is transmitted, through the rod 22, to the outer extremities of the lever 8a and the main spring 1; and the inner' end of the lever is depressed-thereby compressii'ig the upper coils 4a and40 against the upwardly movingV main spring support*until` this action is in turn arrested* by the engagement of the collars 3T with the base plate of the upper .-ipiing. `When` the movements, in either direction, exceed those which cany be accommodated by a corresponding elastic flexure of the supplemental or auxiliary springs, Si or fia-#16), thepositive {iexure of the'inain pringmreinforced and stifl'ened in its resistance by the reactive pressures of the lightly compressed secondary units-is brought into play to quickly arrest and absorb the residual or unchecked portions of ie said movements.

ln the organization which is illustrated in Figs. 13 to 1,6 inclusive the counteracting supplemental spring units are made up of single volute coil 3" placed above the intel'- v lediate flexible portion of the main cross leaf spring 1, and a pair of helical coils 4" and 40b which are positioned vertically below and in axial' alignment with the upper coil. The upper spring is confined between .wo follower plates 20 and 42, and the lower coils are correspondingly confined between the opposedI follower' heads 13b and 42. Each of the follower heads Q0" and 13b are adapted toislide longitudinally on a stop bolt-(marked 17'3 and 28h respectively)- which is secured to the main spring clip T" and is provided with a head that engages withv the opposed follower plate (42 or 42) and limits the opening or expansion movement of the confined spring. In the normal load position of the parts (see Fig. 13) the lower follower plate rests on the top of the axle frame, and the upper `follower plate is held in tensioned engagement therewith by two adjustable stirrup bolt connections 44-44- The# adjacent faces of thefollower plates 20" and` 13b are detachably engaged with the inner ends of the lever arms 8h, and the latter are riveted, or otherwise suitably secured, at their outer extremities, to a triangular spacing block 45, which is pivotally coupled, at .its three vertices, with the axle perch (by the pintle bolt 11b), with the extremity of the main spring (by the shackle links 21h), and withthe main body portion of the vehicle (by the tension rodand-link connections 22"--23b).

lWhen the organization shown in Fig. 13 is subjected to an increased kinetic com pression stress the parts thereof are moved from the normal load positions (Bb) to the positions, C-c, shown in full lines in Fig. 14 and partially indicated in dotted lines in Figs. 13 and 15. In this movement the inner end of the lever 8 is rocked up wardly, thusl liftingl the follower head 20" away from itsl engagement with the central clp support 7", and compressing the upper springl allainst the upper ilollower head t2 which is concurrently moved downward with the main spring by reason of its stop bolt and clip connection (17h-JW) therewith. The movement of the body and main spring` toward the axle support is also resisted, to aismaller degree, by the direct compression of the lower coils L1lb-4U" between the heads lil!) and 42 which are then respectively engaged by 'tlie under side ofthe clip 7l and the u pper face of the axle frame. This lever com trollled liexure of theanxiliary spring unit il may continue until the compression oli the system brings the lower face of the main spring into pressure contact with the cross rib Giof the forked axle perch; after which the further approach of the oscillating meinbers is quickly checked by the augmented bendingresistance of the prin'iary suspension member which is reinforced by the further direct compression of the lower coils 4b and 40h. 1When the increased kinetic stress is relieved the flexed springs will recoil and return the parts toA their initial position ol static balance (l-0); but when this position is reached the connector elements 23 are brought into tenslmied engagement with the .lever and body memliiers, and the upper follower plate 42 is simultaneoru-Ey locked in` fixed relation toitheaxle frame by the stirrup bolts Lll-nlet. lf the momentum of the recoil nioveinente-or any other stress of separationwis sufficiently great to mo rc the body and axle members away from each other from position llw toward the posim tions lik-e (as shown in full lines in Figs. le and 16 and as partially indicated in dotted lines in Fig. 13) the outer ends of the lever arms 8h, and of the main spring l. will be lifted by the pull ofthe connections QTL-23S ctc.; and the auxiliary Sii reboumbchrcl;

springs (4b--10b) will'be compi-essedibetween the head 13 which being carried down by the swinging leve, and the head 42 which is being concurrently lifted by the oppfi.V le

moving main spring clip` Tl. The ela a' restraint thus imposed on the kinetic expansion of the system is augmented by the lesser direct compression of the upper coil Il between the follower plates 20 and if which are respectively fixed with respect to the oppositely moving main sprinnr and axle mi members. ln this action the cooperiuire downward pressure of both of lh i auxiliaryY spring units (4b-40h and ll) on the inirw mediate flexible portion of the upwardly y moving main spring, combined with the sinniltaneous upward pull on its outer end. resists any tendency of tl.'x said main sprung to abnormal recoil, and prerenls any rrlleo ing or expansion of this element beyond its 13" normal load form, under the most 1 -wirf.'

(itl

checking a tnrther abnormal rebound movement.

Figs. 17, 18 and 19 present another exemplilication of my invention, which is quite ditterent in form, but which is substantially identical in action with the double-counteracting` spring construction shown in Figs. 13 to l() inclusive. ln this tourt-h illustrative en'ibodiinent ot my improvements the auxiliary spring system consists of two very tienille lealY springs 3c and 4;, which are pivotally mounted., attheir inner ends, on a main spring clip, 7; and which bear, at their outer ends.v en the opposite faces ol.i the main springl. The intermediate portions of the supplemental spring, units, Bc-el-C, are opi-.1ratively engaged `by the spacer bolts 38e-w38@ which also serve to structurally unite the inner ends ot a double-arin-T-shaped lever trame 8C. rl"he outer extremities ot the lever arms are likewise joined together by means ot' spacer bolts ll, 47, and 26C, which act as pivot pins tor flexibly coupling,` the unitary lever trame with the axle perch links 2l, the end eye of the main serine' l, and the rebound control connections 22C, respectively. ln this constructionthe links LZ2 are carried. at their inner cada. on a riulius arm il@ that is piif'otally mounted on a bracket Li9, secured to the central dilterential gear case of the rear axle; and the elbow pin ci'annectiou between the liz-embers 22L- and i8 is coupled to a pivot bloeit aria 5t) on the inner end ot the leat spring; 3C by means ot' the collapsible chain linl-s When the parts are in normal load position-- as shown in lull lines in Fig. l7-both ot the auxiliary leat springs are conlined. under the predetermined initial tensiorn between the cross head bolts 3S-3t3; and they are so set relatively to the main spring (by shitting' the clip support 7") that the top ot upperauXiliaryspring-pivot-bloclt 5l then in pressure engagementwith the main body traine. ln this position the angular relationship ot the toggle arms. and 485 adjusted (as by raising' or loweringthe bracket support 49) until the linhs 2SC-*25C are under a slight tension.

iinder such conditions of adjustment as have i t been described the functional action ot the organization in resisting.;` disla..'-raei'its from the normal load position is as follows: It the body and axle parts are forced toward each other the lever Atraine 8c is rocked 'from position, t), (Fig. 17) toward the position., c, (see Fig. 19) thus flexing the lower supplemental leaf spring 3 upwardly against the lower side of the main leaf spring l. rl`he resistance thus interposed to the re`ative approach ot 'the parts is reinforced by a direct conun'ession ot the upper supplemental spring 'l" between the body tramewhich is engaged with the pivot block 5l at the inner end ot that springwand the upwardly flexed extremity of the main spring. Under excessive shocks the elastic members l and 3C may be brought into substantially continuous pressure engageInent-as shown in Fig. t9-and when this occurs the lever actuated tlexure of the lower auxiliary sljiring will be arrested; and further approach ot the body and ax'e mein bers will be resisted in part by the continued positive tlcinue ot the primary suspension spring l and in part by the accompanyinu` increase in the direct coinln'ession ot the secondary spring Il". lVhen the parts return to the position ol static equilibrium (Fig. 17) and begin to move away from each otlier-toward the rebound positions E e indicated in dotted lines in Fig. l7the tensioned links 22mm-223C exert an upward pull on the elbow joint et' the toggle linkage 22C--l8 and thus produce an outwariil thrust on the lever bolt 26C which roel-:s the traine S downwardy and compresses the auxiliary springv et@ against the upper tace of the main spring` l. This movement carries the lower bolt head. 38, away from the auxiliary spring): il, but the latter is not only pre vented from expanding beyond its initially flexed position but is subjected to some added compression by the pull of the linlr con* nectious 23C en the inner overhangine` end ot its pivot bloclr support 50. lt theirecoil and rebound stress is very severe the upper supplemental spring may be 'flattened out into substantially continuous contact with 'the top surface ot the inaiu spring. and the ley-er traine will then be locked against tui`- ther movement relative thereto; and any further separation of the body and axle members will then be very strongly resisted and quickly checked by the continued positive tlerure of the main spring-#which is beine' moved away from the axe member at its center and ends and pressed toward that member at its intermediate flexible portions-and by the cooperative bending of the lower simplemental spring` 3 under the action of the rebound check connectionsl 226-230-1981.

lill et the shock absorber organizations thus` tar considered are primarily designed tor use on cross leaf spring` suspension .systems. l wil now proceed to describe cc"- tain other illustrative emliodiments ot my 5' cated by dotted lines in Fig. QU.

intention which are more particirarly adapted to different forms ot side leali springA supports.

The construction depicted in Figs. 20 and "2l conipriscs a main side-leatv-siiring unit ot the full elliptic type, and a lever-actuated system couriteracting-snpplemental springs that are operatively interposed between the terminal eye connections at one of the apices of the main spring. The lever meniber itset consists of two side arms S'lw-S that are riveted or otherwiseintegrally secured to a triangular block lld; and this block is pivotally mounted, on the cross bolt lb in the 'forked end ot a bracket 52 which is bolted to the extremity ot the upper semi-elliptic leali eeinent lss. The side arms Sl-Ql are also joined togetherl by the spacer bolt l'll, which to s a pivot connection between the lever and the eye end of the lower semi-elliptic leal.t element ls, and by the cross head 3S that engages with the lower to`. lower head 20d ot the supplemental compression spring,` 3d. The inner ends oli the fever arms are curved or recessed to form hooks that are adapted to engage with a cross pin', 13, which passes through the lower eye ot the auxiliary eXjansion spring; 4". The upper ends ot the two supplemental springs il and -l-fl, are both supported on the inain-epringnbody clip 7d; and.` are held under predetermined initial tensionthe one by the stop bolt il?. which prevents he compression spring from expanding, and the otherby the stop bracket. Q8, which aso engages the cross pin lll and prevents the expansion spring -ll from contracting, beyond the normal load position shown in Fig'. Q0. The lower extremity of the lever traine block Lil-5 is flexibly coupled to the main body clip (7d) by means of the toggle link` arms 22d-*48% and the shackle and strap connectors Q3, which are so adjusted as to maintain these parts in tensioned engagement when the members are in static balance position (1S-b).

l/Vhen the system last described is subjected to a compressive shook, or other kinetic stress, which forces the two sides (1S and lss) of the elliptic spring,` toward each other, the lever frame 8d is rocked in a counterclockwise direction and the parts assume the positions C-c that are shown in full lines in Fig. 2l and are partiallyT indi- This moreinent compresses the supplemental spring 3 until the central boss ot the lower itollower plate 20d engages with the lower side of the clip support Td; and atter this occurs the further approach of the body and axle parts is resisted by the continued positive flexure of the main spring elements alone. Then the parts return to normal load position the hooked ends of the arms 53h-8d engage the cross pin 13d, and the lever body connecmarrone tions, QQfl-QB, etc. are brought into opera tive relationship; and any rebound or separation of the spring connected members,` (from the position lmtftoward position EHe) imposes an outward thrust on the link 22d, thus rockingh the lever traine S in a cloclewise direction and eiqiztinlilig the tension spring,r l, until the cross pin l5 is brought into contact with the upper :tare of the main spring),v element lA (as shown in dotted lines in Fie". Qd). rthis clockwise rotation of the lever 4traine torres the ends of the main` springl elements. lSH and 1"", away 'from each other, and thus prevents the latter troni recoiling beyond an nnstressed or unloaded position and becoming; subject to a negative .lle-ture; and when the cross pin 18 engages with the lower niain springr member the lever traine` and chassis parts-a and the seniielliptic leal elements on which they are supportedare substantially locked against further separation by the tension of the tightly stretched band In this constnuction--as in the ones pre Vionsly considered-I preferably provide a rebound check supplemental spring unit which has a substantially gri-eater resistance coeliicient than the auxiliary compression unit; and I thus obtain n more powerful restraint, and an accelerated retardation, oi' the rebound movements as contrasted with the compression action ot the system. The increased resistance coeliicient ot the tension spring ld is obtained, in part by making;- the Coils thereof ot smaller diameter (and il' desired of stiffer material) than the coils of the compression spring l, and in part by so proportioning the rebound connertions (221-4Sl)3l) between the lever and body members (45 and Td) that a given morement, ot separation rorls the lever through a larger angle, and produces a correspondingr; greater flexure of the auxiliary springt, than is obtained by the saine linear movement ol. compression. And in this constructioii--as in the irst and third illnstratito embodiments of my invention-thc ratio olf the opposite angular movements off the lever frame may be varied as desired by shitting the pivot bolt connection Ztl to (lith-nient holes in the lever block el-il.

Figs. 22, 23 and Bel illustrate another application of my iinprtn'ed .supplemental spring organization to a side lent sprintf oil the semiclliptic torni. In this c:\'ein1:iliira tion of my invention the counter artin; l anxiliary springs consist ot two highly resilient leaf springs, il and l which :ire bolted, at their outer ends, to the intermediate legi' portion oit an l. shaped lever nienxbcr t5, and which are respectively engaged, at their other extremities, with a body bracket, T. and with the lower end ot the linlts Qt" that are suspended 'from the said bracket. The downwardly turned foot and toe portions ot' llfl the L shaped lever :frame are pivotally connected to the forked` endof a curved hanger iron 52e (by the pintle bolt l17e) and to the adjacent eye of the main spring 1s (by means of the pintle bolt 11e and the shackle links ML-21e); and the upwardly turned heel portion of this frame is flexibly coupled to the axle member of the vehicle by means of the cross bolt 26e, the rigid strap 22, and the intervening turnbuckle-chain-and-sheave connections 2353- The inwardly `projecting leg portion oi` the lever is forked, or divided, to receive, and closely embrace, the loliate edges of i the supplemental leaf springs, 3c and 4e; and the extremities of these forks are provided with elongated and slotted heads 54.-,54, which are adapted to engage the projecting ends of pins 55 and 56 that are carried by suitable clips on the central parts of the said springs, and which limit the expansion or recoil movement of these elements in the manner hereinafter ex plained.

The mode of operation whichA charac terizes the multiple leaf spring suspension shown in Figs, 22, 23 and 24 is essentially the same as that of the analogous cross leaf spring construction which is depicted in Figs. 17, 18 and 19. In the normal load position of static balance (13#6) the supplemental spring elements are confined under a predetermined initial iiexure between the bracket 7e, and the lower end of the link frame 28"; and in this position of the parts the pins 55 and 56 are in engagement with the opposite ends of the slotted head 54; and the flexible connection 23e is under a slight tension. If now the body and axle parts are forced toward each other the lever member Se is rocked in a counterclockwise direction, from the position shown in Fig. 22 toward the one indicated in dotted lines (Cl-0) in Fig 23, and the upper auxiliary leaf spring 3e is' progressively and increasingly flexed, until the heads 54 impinge against the under side of the body iframe. The upward movement of the lever also raises the other auxiliary' spring 4- by the engagement of the pin 56 with the lower ends of the slotted heads 54-511 thus preventing the expansion or recoil of this secondary resilient element that might otherwise be permitted by the collapse of the suspension frame `28". In order to enl sure the proper closing movement of this 'frame I preferably connect the lower links thereof to a pivot clip on the end portion of the member 11", and provide a light spring 57 which tends to press the upper links outwardly as the body frame moves toward the axle. When the parts rebound above the normal load position the relative separation of the body and axle parts impose a pull on the rebound-check connections (22 6c, in a clockwise direction and carry the parts toward the lfull `line position (ICM-e) shown 'in Fig. 22?. This movementimposes a greatly increased 'flexnre on the lower sup plemental spring ll'---thc.inner end-of which is now heldin fixed relationship with the body by the tensioned support 280-and also carries the upper supplemental spring 3 away from the body bracket 7 e, (by the engagement of the lever heads 54-54 with the pin 55), thus preventing` the `said spring from assisting in the upthrow of the body by a recoil action. The clockwise displacement of the lever also depresses the end of the main spring relatively to the body pivot bolt 47, and thus tends to reduce the recoil of the primary suspension member, and to definitely limit the reflexing or expansion of this spring beyond its normal load form, under excessive rebound stresses. These concurrent and cooperative motions of the lever and spring members will ultimately bring the lower face of the element le Vinto extended pressure engagement with the upper side of the main spring 1S, and also bring the pins 56-55 into superimposed contact with the upper side of the lever heads 54 (as shown infull lines in Fig. 23); and when the parts reach these positions the interconnected lever and spring members are locked together; and any further separation of the body and axle frames is very strongly resisted by the semi-elastic yielding of the chain 23e and a very slight` additional bending of the interlocked and mutually reinforced and stifiened suspension elements ls-fiL-te--SB etc.

All of the constructions thus far described are structually characterized by the use of a single lever for reciprocally actuating and controlling the reverse ilexures of the two supplemental spring units that respectively oppose the compression, and theiexpansion. or rebound, ot the system. But my invention is not restricted to such a `structural combination: and I will now describe some additional illustrative.embodiments thereof, in which separate lever members are provided for actuating the counteracting auxiliary springs, and subjecting them to any desired degree of relative flexure, when the body and axle members are displaced in opposite directions from the normal load position oli' static equilibrium. This species oi construction-like the one first considered-may include a wide variety of different forms, that are particularly adapted for use with special types of main spring suspensions or with special designs of chassis iframe construction.`

The multiple-lever-auxiliary-spring combination illustrated in Figs. 25, 26 and 27 is primarily designed for use in conjunction with a three-quarter-elliptic, or semi-elliptic- 23--26e ete), which rock the leverframe,scroll, spring support. In this exemplifica- Q fi icc

I :ii

liaryspr frunitcoinlfvrises a par of helical coil tei ion sprlngs fil-@lf2 which .are symmetrically dispbs lnonelon each side ol the spring 3l d and ,li are connected, at"r their ely renntscs, with the body frame clip Tf a' fd ivithtlie outer end of a second lever58, tl'iat isa'lso 'ifvoted on ythe body bracket 59. Theyadj cent terminals or' the tviio sibrine i itsl'r and 4f; are flexibly connected bythe sh lile links VC30-"460, in the manner bestshbWninAthe det `o'ss sectional vieiv or' 27 andtheintemediate partof the lei/*e1 58 isfoperatitely c'iipled' lto the a'Xfle i ilraiiiezby meansolf the reeker arms 222 and the pin and sl'tconne'etins, Q'Gf and 231, as shonfn in setftion` at thel right hand ot Fig'. Q5.

The functionalaction of the double-lever interactiii'gy sprine'- mechanism last de-V scribed is substantially the saineV as that of the single lever combinations that have been `1)reifioisly explained. their the parts a're forced from the normal Aload riiosition (Bw 7)), shown in Fig. QLtWa'rd :thfe Position' of compression depicted in l* ig; 26, the lever 8f is rocked nvvardlya andthe supple-- mental spring'f is subjected yto an increased tlexure, Which"beiids it into al gradually increasingarc et 'o ontactavith the under side oft thebody and thus interposes a ,L gfeometrically progressif@ elastic resistance to the relative approach of the spring supported meinbers. `During this inovei'n'en't the second lever 5S; and `the reb'o'un'd check auxiliary springs d2 are held `in fixed relation to the body frame by the linke leon-60'; and the coils Litirethereby prevented from contractin*Vr beyond their initially tensioii'ed positi." i. But When lthe body and axle meiiibers rebound or separate frdin one another-from the position' ofistatievbalance (iB-L) tou'aiird the expanded lpsition l(=E-e) `which ris indicated in `dotted llines in' Figi; 25`Jtl1e pull olkthe tensioned link connections QQ rocks the lever4 5S downwardly; and the subplemental springs 4f are subjected to a rapidly increased liexre until the 1end of the lever comes in eontafct Withthe u, Aper face 'of the main spi-.ing l5. The downward 'metoii of the `member 58 carries with it the shackle links 60-60, and the end of the auxiliary leal'spring 3f connected ltheretoland this action notnly preventsanyrecoil of the said leaf spring fromits initially 4flexed con# dition;` but actua-11yfimioosesseine additional iiexuie thereon and thus ena-biesit to effecis bolted rigidly to elastic resistance eoellicieilty ot the lever-art u ated-spring elements. tiS-fll-ll and ltl-f-il. should be such that the greatest rebound Stresses, to which the system may be subjeeted, will have been substantially compensated and absorbed by the i, reine expansion 1no\:en`ien`t indicated by dotted lines (lil-(2) in Fig.f25; for when this rnoveinent has taken place, and thc end ofthe lever 5S has engaged the stiff central portion ol the inain spring, the eiastically suspended parts will be locked against further separation by the non-resilient connections between the bracket 59 and the main springaxle block.

The kinematical arrangement ol elements illustrated in Figs. et'seq. is capable ot performing another function, and securingl an added result, that has not heretofore been described in connection with the ronstructions depicted in Figs. T to 2l: inclusive Then this last described eonstruction is subjected to kinetic compression the pintle bin connection 26 slides outwardly .in the slot 232 which is of such curvature and contour that its sides arealways inclined at a, small angleto the kinematic anis of the arms if. then the return movement begins the pin QGf-ivhch is preferably made of rectangle lar cross section as shown in Fig. brought into pressure `engagement with the lower side ot' the slot 23f; and the i'rictional resistance to its inward and backiifard Inovenientto normal load `position (Fig. Q3) iinposes an "immediate tension ou the link connections 22E that series to retard or lamb the recoil and return of the parts toward normal load position. This tension in the links QQf also serves to exert a downward pull on the lever 5S and thus subjects thc springs 4F to what has been termed a brenormal increase in stress-4i. e. to an `increase that is initiated belore the parts have been retiirned to normal load `positiouwaiul if this precursory increase is ol snicient magnitude it will result in a corresporulingrly advanced movement olE the lever. and an accompanying elongation 'ot these springs. Such an advanced movement ol the lever member 5S also pulls the outer end oll the leaf spring 3f aiviy from the body 'trame before the said spring has returned to its normal load position, and thus further rediicies the effect et that spring;V in producingl a rebound or upthrow of the vehicle touneau. The magnitude of these iinelimiiniry or prenorihal attions ot the rebound-checktill lill

ltlll lll llo

lill

Ll ll system may be widely varied by altering the lorin of llie slot 2drso as to vary the angle ot' :trictional contact between the lo\ver edge of this slot and the pin lfwand by providingl friction washers, or plates (il, that are `intei-posed betnf'een the ends ot the urnas und the adjacent faces' oll the lever fit1. :uid :ire maintained in any desired pressure cngr'iuniiucnt with these parts by an adjustineut ott-bc nuts on the ends ol the pin Qbf. v

lligs. it and illustrate another tivolererdoublc-springg exemplitication olf my improvenicnts as applied to a rear cross leaf spring;` suspension ot a Ford car. In this construction the conipression-resisting supplemental sp1-ine' consists ot a. flexible leat clement` 3e' which is bolted at its outer end to a short lever Rand is engaged, at its in ner end, by the upper cross bolt ot a clip that is secured Vto the central portion ot the main spring. The lever 8e is roelrably mounted on the axle perch bolt lig and is recessed at its outer end to receive a bridge bloei: 62, that pivoted at its inner eX- treniity on the bolt llg (between the recessed sides ot the lever). and coupled at. its outer extren'iity to the end eye ot the main spring by `means of the shackle links 21g. The reboundcheclz-au-iliary spring` consists ot a volute coil lg which is confined, under a predetermined initial tension, between the main spring` clip 63, and the cupped head ot a lever 53g, that is pivotally supported on a. bracket, 59g. bolted to the differential case otl the rear axle. The intermediate part of the lever 58g is coupled to the main spring` clip ig by means ot the lirl arms, 22g, and the split block and bolt connection 26g Which slides on the seg1nental ly ribbed portion 23g ot the lever member (see enlarged sectional view of Fig. 30).

' The operative elements ot Vthe combination now under consideration are so proportioned and adjusted that in the normal load position ot the partsshown in full line-s in Fig'. 24S-fthe bridge block 62 is in pressure Vengrajgement with the outwardly projecting? recessed end ot the supplementalspring-lever 0"' rests on the inain aide case or traine. 'lbe suspended parts are thus held in the position ol static balance (I3-7)) by the combined reaction oit both ot the initially flexed auxiliary springs 3f. and lf on the main spi-inn' shackle and clip connections 2l, 7g and 63. In this position ot the parts the blo/cl: 26g is drawn into Contact with a .fixed sten er shoulder at the inner end ot the ribbed ruidevvay 23g; and the central portion o'lE the initially flexedsupplemental spring; S rests lightly on tbe top` ot the clip 68. lt" now the body and aule parts are `lorced to lard each other, by a kinetic increase in load stress, the pressure engaged lever inem- "tion, (E-c), shown in Fig'.

and the head of the lever bers, t--'-(i2. are rocked in a counter-clochwise direction und the auxiliary leali' spring: 3 is correspoiuliugly `flexed to the torni shown in. dotted lines in Fig. 28. The relative approach ot the bod)r and main sp1-ini;` toward the :irate 'traine also rcsultsiu a direct compres yion ot the second auxiliary spr-ingr elf. between the plate (SB lever member 5W; and this suliplemcuts the action ot the more strongly llcxed auxiliary clement 3 in resisting and checkingl the conipression olil the system. During,- these movements the block connection 2G slides outwardly on the stationary lever men'iliers Slg-23g until it engages with a stop or shoulder at the outer end of its `quiden'av-as shown in dotted lines in Fin. 2S and thus arrests further approach ot th(` main spring and axle parts. lVlien thereliects ot the kinetic increase in loa-d have been absorl'iedN and the elastically stressed members begin to recoil lroin their compressed position, the split bloei; connection is i'rictionally engaged with the lever gruideway, 23g: and the link connection 22": then exerts a downvard pull on the main spring and body members.v and a reverscly directed or 11p-- ward pull on the lever 58g: and the auxiliary coil l-g is thereby subjected to a prenoruml `increase in 'flexural stress that reacts against the `.main spring, and the concurrently flexed supplemental. spring 3g, to damp or retard the return ot the system to normal load position. TheY angular relation of the interconnected elelnents is such that the pull ot the links, 22g, on `the block will eradually move the latter inwardly toward the lever 'fulcruin support 59g and `thus geometricallv increase the effective restraint action of the lever-actuatedspring 4g, as the recoil movement continues. until the block engages With the end ci the ribs 23g. It the rebound or expansion stress is suiiicient to carry the parts above the point ot static balance (lil-7)) toward the rebound posi Q9, the volute coils ot t-he auxiliary sprinawill be 'further compressed against the lower side ot the clip plate 63: and this action will exert au upward `thrust on the outer flexible portion ot the main siirinej that Will litt the end thereof-(bvrockingA the pivoted bride'e (i2 away troni the lever ll -and thus serve to arrest any sensible retlefiingr or eXpan- ,sion o'l'l the primary suspension nien'iber beyond its norinally loaded ttorm. This upward moveini-Pnt1 of the clip 63 and the main spring); l. will also increase the inital flex ure ot the aiiixiliary leat spring. 3e'. and thereby cause this element to supplement the action ot the lower spring, 4H. in re- .itrainiiur and f 'heclrinfr rebound. Then the volute coils ot' the sprinn; 4i* have been coinpressed to their nested or solid condition, the lever, 58g, the main spring l, and

and the lixell i the tivo' shlipleniental springs 3g and ll?, are all locked together into a mutually reinforcing semi-elastic group of elements that will very strongly resist any further separation ottlie body and axleparts.

Figs. 31, 32 and `33 illust-rate another multiple-levencontrolled system of opposed, or counteracting.supplemental springs applied to a semi-elliptic side leaf spring suspension. In ths embodiment of my invention the auxiliary resilient elements comprise tivo oppositely flexed lcai' springs 3 and 41K that are respectively secured to the rigid lever members Sh and 58h, and are engaged', at their `reverse extremities, With the central andyendportions ol.1 the main spring 1S. Theiloiver` member Sh is pivotally mounted o'n the end `of the body scroll iron 52 and is provided With a stop flange (il, that limits the clockwise rotation ot the lever on its mounting, and also with a slot 62h `that receives the endsof the lower cross bolt of a forked shackle link 21h. rlhe upper cross bolt of this link is engaged with the end eye of the main spring 1S, and the link is also connected to the end eye of the upper` rebound-cbeclaiixilia1y spring by means of a third pin bolt65. The lever 58h-Which controls the flexural movement oi the last mentioned spring-islexibly connected to the body bracket 59, (by means ot the shackle links (i6-66); and is operatively coupled to the axle framelby the swinging armsl QQL-QQh, and the slidingsaddle and guide membersQh--Qlh) in themanner previously described inf detail in connection with Figs. 2830- The body bracket 59h is provided With a stop boss 67, Which engages With the interinediate portion of the upper auxiliary spring 4h and maintains the latter under a predetermined initial position when the parts are in the normal load position shown in Fig. 31.

The kinematical action of the last described organization is essentially thesame as that `et' thecross leaf spring construction shown in Figs, 28 and 29; and the relative positions assumed the parts in resisting and checking both compression and expansion movements of the systemand in counteracting recoil and preventing nega* tive lexure or reverse bending of the main spring in connection therewith-are so clearly illustrated in Figs. 32 and 33 as to render any further explanation of this action unnecessary.

Fig. 84 depicts a structural modification oi" thege'iieral form of lever-spring mech anismthat is shown in the three preceding illustrations. This modilicationis designed for use on a three-quarter-elliptic spring suspension, and comprises tivo auxiliary leaf springs, 3l and 4i, which are respectively secured to two lever members Si and 58% and are lexiblyengaged at their eye ends With the body oit the vehicle and with a shackle link, (35i, that is supported :trom the lever 8i. The lever member Si is pivotally connected to the eye end ot the main spring l by the cross bolt lli, and to the extrcinitv ot the quarter-elliptic, or scroll, spring il, by the lorked shackle link 2li. The lever meinber 518i is pivotally mounted, at an intermediate point et' its length, on the bracket clip 591 which is secured to the axle iframe; and the inner end ol the said nicnihcr is operatively connected to the body 'trame by means of the swinging rod Q; which is detaehably engaged by a split collar Qdi that loosely mounted in the conical recess 23* at this end oit the lever. The inucr end portion of the auxiliary leaf spring li is rigidly coupled to the central portion ot the other supplemental spring il by the links (i.

Then the parts are in the normal load posit-ion, indicated in full lilies in Fig. 3l, the lower end of the shackle connection (i bears on the adjacent upper 'face of the main spring; and both of the auxiliary springs` -l and 4i are maintained undei mutually rcactive initial tensions/by the cross connection G01-which cooperate in balancing the static downward pressure ot the body on the ends of the suspension elements Bi and lss. If now the body7 and axle parts are l'orced toward each other, by an increased kinetic load stress, the lever Si will bc rocked upwardly and the upper supplemental spring 3 will be flexed into a ln'ogressively increased arc of Contact with the underside of the body frame-as indicated b v the up per dotted line c-c of' Fig. 34 and the mutual approach of the spring supported members will concurrently produce (by thc action of the connector 601) a complemental flexure of the lower auxiliary spring JJM-as indicated by the lower dotted line e-c of this same ligure-and these concurrent ilexures of both supplemental springs will cooperate With the action of the main spring supports lE and 1"*S in effectively constraining and controlling the compression o'f: the system by a geomctrically increased elastic resistance thereto. As the parts move toward each other the rod 221 will slide freely through the split clamp block 261; but when the reverse movement beginsunder the recoil stress of the compressed spring supportsthe said block will be drawn into pressure engagement with the inclined Walls of the conical recess 23H and will grip the surface ol the connector 221; and the continuation of the return movement will produce a frictional drag on the axle block and main spring assemblage which will resist this movement, and will also produce, or tend to produce, a countercloclm'ise rotation ol the lever 581, and a corresponding bending of the auxiliary leal springs 4* Lil and 3i, that will retard or damp the recoil action and reduce or eliminate the subsequent rebound or upthrow beyond the normal load position. But if the parts are subjected toan expansion stress that will move them beyond the point oi' static balance B-Z the pull of the connector 2T- which will be brought into positive engagement with the lever 58i when the nut at the lower end oi this rod comes in contact with the said lever)-will bend the lower auX- iliary leaf spring into contact with the upper' face oi' the main spring (as shown by the lower dotted line eme of Fig. 34) and this downward movement will be communicated in partito the upper auxiliary leaf spring 3i by the pull of the links 60i and will correspondingly bend this element away from the upwardly moving body frame (as indicated by the upper dotted line c-c of Fig. These concurrent ilexures of the two supplemental springs will interpose a geometrically increased elastic resistance to rebound movement which may be made much greater than the reverse resistance,` to closing .or compressive movement, by a suitable proportioning oit the power arms ot the two lever members 58i and 8i; and the downward pressure ot the flexed supplemental spring system on the outer portions ot' the main spring ls will tend to directly restrain the upthrow oi' the primary suspension member and deinitely limit the re- 'tlexing or expansion thereof by extreme separation ot' the body and aXle frames.

In Figs. 35, 36 and 86 l have illustrated an application or' the second species of my invention to a cantilever spring suspension `for the axle member. ln this type of snspension the primary resilient element is a substantially fiat leaf spring, 1X, which is bolted, at its base, to the body trame and is pivotally connected, at its fiexible end, to a bearing block on one of the axle trames. ln applying my invention to such a construction the main spring is somewhat shortened and stiened-(e. g, by cutting` off the singie leaf portion which is ordinarily con nected to the axle block)and is coupled to the vertically oscillatingr wheel support by means ot a rocking lever member 8k, and the pintle bolt and clip-block. connections ilk and 68. The lever 8 carries a supplemental leaf spring 3 which bears at its free end on the upper surface of the main leaf spring 1X. A second auxiliary leaf spring, i, is secured, at one end, to a rigid base 58k, that is pivoted on the body bracket 59k; and this spring is also engaged, at its opposite tree end, with the relatively stiff base or body portion ot the primary suspension member.

The supplemental springs 3k and t are both maintained under predetermined initial fleXures-which cooperate in the support of the parts in static balance under normal load pressureswby the contact of the enlarged head of base member 58k with the body frame, and the engagement between this head and an upwardly projecting lug 69 on the lever element 8k. The two lever members, 58k and 8k, are also conjoined, on opposite sides of their fulcrum supports, by means of the oscillating piston and dash pot connections which are best shown in the sectional views oi' Figs. 35 and 36a. These connections comprise a pair of arms 22k-221 which are pivotally secured to the head of the lever member 58 and which terminate in a cylinder 26k; and a hollow plunger 23k which is pivoted on the boss 70 of the other lever 8k. The lower end oi the plunger element is provided with a loosely litting cap 7l which is held inV place by a light spring 72; and the space between the cylinder and plunger parts is lilled with a heavy oil or light grease like that used in transmission gear cases.

The operation of the above described organization is as follows: WVhen the system is subjected to a kinetic compression, the body and main spring will move downwardly with respect to the axle, and the lever 8k will be rocked in the direction of the arrow 'L -c, thus bending the spring 3k into a continually lengthening arc ot contact with the top oi the cantilever support lx, and interposing a geometrically progressive resistance to the compression movement. This action will continue until the lever 8k has moved through the angle bc, and the supplemental resilient element 3 has been tlattened out against the upper surface ci' the main s ring element lx ;as shown in dotted lines, (l-0, of Fig. 34and after this occurs the further approach oi' the body and axle parts will be very strongly resisted by the unitary ilexure of these superimposed and mutually intel-locked and reinforced suspension members. During the compression movement the cylinder 26k will slide downwardly over the plunger 23k; and the valve 7l will open to allow the liquid within the plunger chamber to flow into the lower end ot' the depressed cylinder. When the reverse movement begins the valve 7l will close, and the body of liquid thus trapped between the ends ot' the members 26k and 23 will act as a liquid clutch coupling which will exert a tric-tional drag on the separation ot the body and axle parts (with which the members 22k and 23 are respectively connected) and which will also transmit the recoil motion ot the lever-spring-unit- 8k to the lever 58 and thereby impose a prenormal stress on the auxiliary rebound-check spring Lik. These actions will result in a pronounced slowing down or damping of the return of llU `the viscosity ot the fluid.

longitudinally locked connections,

the compressed suspension members to the position ol initial static balance; and these retardation elfects can be regulated by controlling` the leakage of the dash pot liquid Apast the" closed valve 7l, either by providing a `small hole 73 therein, or by varying lVhen the parts have returned `to normal load position the plunger 23k will ordinarily have reached the "bottom of the cylinder 26h; and any rebound or ex uansion movement be ondithis i jected to a greater tlexure than the supple- `mental compression-check-unit 3k; and its eilfective flexural length is also progressively shortened as the expansion movement coninues-as shown in Fig. E36-so that the expansion of the suspension system is more strongly resisted and more quickly checked than the compression thereo'l'; and if the rebound orseparation of the body and axle trames is excessive the three superimposed springs 4, 8k and ltwill be locked together over a considerable part of their length and will then act as a strongly reinforced and very stiff unitary restraint element. And it willvbe further noted that in this movement of reboundas in the reverse movement of compression-the pressure oit the supplemental springs on the upper couver;v surface ot the main spring tends to straighten out, oriincrease the curvature, oit the primary suspension member, and thus limit its rei flexion or expansion under recoil stresses.

All of the previously described embodiments of my invention have been characterized by the use of lever elements for effecting and controllingwand in general magnifyingthe flexural, or elastic restraint, action of both the compression-resisting andthe rebound-check supplemental spring elements. iiut my invention may `be `also utilized in other structural combinations in which either one or both oit' the auxiliary suspension sprino's may be directly actuated by the approach or separation ot the relatively movable chassis parts, without the intervention ot any lever connections, or equivalent devices. The final sheet of my drawings illustrate several forms ot this third species `of my improved multiple spring construction as applied to different types of main spring suspension systems.

Figs. 37 and 38 depict a cross leaf spring support, for the front axle ot a Ford car, in which the end of the main spring l is di rectly suspended from, and supported on,

vwhich is adapted to engage with the base plate 75, andprevent the supplemental suspension coil 3l from expanding beyond `its position oi predetermined initial tlexure; andi-his head `is provided with an arcuate slot 621, which engages the central portion oi' a cross bolt, 7G, that connects the upper ends oi the shackle links 211 to the forked cytot a radius or guide arm 7T. The lower cx- `tremities of the shackle elements are coupled tothe eye ot the main spring l by naans ol a second cross bolt, and are also coupled to the end ot another auxiliary leaf springI -ll by a third cross bolt (551. The inner, oi base, portion of the supplemental spring l* is bolted to a short lever 58, which ilexibly coupled to the axle block 591 by the shackle links G61. and which is operati vel v connected with the stiff central portion or the main spring l, by means oli the swing-- ing links, 22l221, and the grooved block. 261, that slides on the upper leal. of the ,said main spring.` The lever member 581 is also provided with a boss or` lug Gil which is adapted to make contact engagen'ient with the axle trame and limit the downward movement ot the lever on its inner pvot support.

lVhen the members are in normal load position, the auxiliary springs 31 and il are bot-h maintained under a predetermined initial tension or strain which is suilicirnt to balance the downward pressure ol" thtl load on the shackle connections 521. Vlihen this load stress is increased the body and main spring move toward the axle traine-- as `indicated by the dotted lines Cna ol F ig. Iii-and the supplemental resilient` elements are concurrently subjected to an in creased iiexure; but the major portion ol the resultant elastic resistance is furnished by the, compression et the volute coil spring 3l. This direct compression oi' all the elastic suspension members may continue until the lower edge of the radius` guide arm 77 comes in contact with the base .of the axle perch on which it is pivoted; but after this occurs further tlexuie ot the auxiliary springs 3l and di arrested, and the continued compression oi" the system is restrained and controlled by llal bending ot the main spring alone. lhiring there phases of the operation the lever member 581 is held in fixed angular relation to the axle frame; and the arms .21 and the bearing `block 261 `move outwar(ily-under the joint influence ot gravity and ot a light lllfl llo take up spring 57l-toward the inclined position, c--c ot Fig. 37. When the compressive movement is arrested and the parts begin to recoil toward normal load position the goroved block 261 grips the surface ot the upwardly moving main spring, and exerts a pull on the arms 221 which frictionally resists this reliex upward motion ot Jthe primary suspension member, and

which also tends to rock the lever 58* in a clockwise direction `and thereby increase the positive lleiture ot the auxiliary leaf spring al. This action restrains and retards the upthrow of the body traine, Without interlering with the tree return ot the outer shackle link connections, (211-17 1), and of the auxiliary coil spring (31), to the normal load position. As the prenormal action of the rebound-check mechanism continues the block 261 is gradually drawn inward until it is brought to rest, in normal load position, against the end ot the central leal plate ot the main spring (as shown in lull lines in both Figs. 37 and 38) and when the body and aide parts are further separated, the lever 58I is positively rotated on its shackle pin support, and the auxiliary spring al is rapidly flexed into a progressively lengthened are of contact with the lower 'tare of the main spring (as shown in Fig. This action produces a geomctrically accelerated increase in the elastic resistance ol the system to expansion movements, and quickly arrests any displacement ot the body Jframe under the influence et rebound stress. The rapidly `accelerated reactive pressure of the lower spring against the outer flexible portions ot' the main spring also results in an upward nnivement ot the eye end oil the Vprimary suspension member which is permitted by the liree upward motion ol the shackle and guide arm connection (2li-77) in the arcuate slot @ilu-and thus prevents the coinplete reliering and occasional reverse bending to which that member is usually subjected b y the upthrow ol" the body iframe.

Figs. 39 and l-O illustrate another application ot the last described species of my iinprovements to the rear cross leaf spring support ot a Ford car. As here shown the compression resisting supplemcntal-spring, on which the end oit the main spring l is directly suspended, consists ot a pair ot coaxial coils Sin-3m that are mounted in a closed casing Which is partially lilled with a heavy oil or grease. his casing comprises an outer tubular member 79, which is screwed into the recessed head m ot the axle brake drum perch, and is provided at the top with an inturned flange and with a pair ol? vertically slotted side arms SiO-80; and an inner cap 20m, which has an upwardly projecting head 81, and which is also provided with a spring closed vent 82 that of the spring valve 82.

opens outwardly for the purpose of permit-` ting the tree escape ol air from the casing. The cap head Sl is engaged by the central portion ot a long cross` bolt, 83, Which passes through the slots (52m of the arms Sil-80, and is connected at its extremities with the vertical links 17m-17m; and these links are connected, in turn (by another cross bolt) to the inner end oit a rocking guide arm 77m and to the upper ends of the main spring shackle links 21m-21m. The lower side ot the main spring eye-(Which .is pivotally coupled to the links 2l-2l)is engaged by the liexible extremity ot a long live-leatspl'ing fl, Which is secured to a nonresilient lever member 58m, and is provided with a button clip 67!" that normally rests on the main axle frame. The lever 58m is pivotally mounted, at an interinediate point on its length, on the main spring clip 7m; .and is operatively coupled at its inner extremity to the axle case bracket 59' by means ot the sliding bolt and Wedge grip connections 22m-26m.

rlhe functional action ot the rear axle suspension systenn shown in Figa. 39 and 4:0, is similar to that of the front axle suspension last described. )V hen the body and axle members are moved toward each otherw'irom the normal load position shown in full lines (I3-2)) tovvard that shown in dotted lines (CMU) of Fig. 3S- the supiileniental springs 3m and 4m are both increasingly tiered until the guide arm TTY comes into engagement with the lower part ot its axle perch support (or the cross bolt 83 engages with the bottom of the slots 62m) but after this occurs the compression. ot the coils mmflm is arrested, and any lurthcr approach ot the relatively movable parte is resisted by the continued cooperative 'tlexure of the mutually connected main and auxiliary leaf springs l. ad -lfmz and this second phase ot the closing movement may continue until the innerends ol" the lever arms 58m strike the top ot the axle bracket 59m. `ln the connnession ot the sys! tem the. rods 22m slide freely tliroi'igh the split cone grips 26m; but when the return movement begins the said grips are 'frictionally engaged with the said rods` and the recoil action ol the systei'n is retarded and daniped in the manner heretot'ore ei;- nlained. ln the case ot' this construction leaf spring` members. l. and 4m, by the prenormal action of the rebound-check-elenien is supplemented by a pneumatic prersnre check on the recoil ot the auxiliary coil springs 231, which is produced by the action lVhen the coils are compressed by the downward movement ot the cap 20m the valve opens and allows the air above the liquid packing` in the lower cell to escape; but when the compression llU 

